Estimation of the sound in ship cabins considering low frequency and flowing noise characteristics of HVAC duct

In order to reduce this difference, the sound attenuation level in a duct, sound transmission loss through the duct, and the end reflection factor of the duct end are defined experimentally with ducts used in the naval vessel. In addition, the breakout sound of a duct caused by flowing in a duct is also defined through the experiment. The indoor noise of the typical cabins of the naval vessel is estimated by applying the sound characteristics defined in this research. The sound characteristics are verified by investigating the difference between the estimated and measured sound pressure levels of the typical cabins.